Demand-indicator.



W. E. PORTER.

DEMAND INDICATOR. APPLICATION FILED JULY'L 1914.

Witnesses: Inventor? 17 Willard EPol-terf merits or indicators, and in particular to inhereina'fter. 1

tion are indicateclin the 'inittently mode of the demand of an elec-:

trical installation and uv record retained O'lI proportional to the speed of rotat on of the f the inamm un demand so measured;

. actuator having an im ill VILLARD E PURTER, OF LYNN, MfixSSACHUSETT3, ASSIG-NOR TO GENEEQRL ELEGTRIU CG'MJPAITY, A. CORPORATION GE NEW. Y-CTZi.

nnrczinn-rnnicnron.

1,138,? $65, I Specification of lictters Patent.

pplioetion filed-July 1, 1314. Serial No. 8%,418.

To aZZ whom-L it may coriccm: j t?) indicate the maximum movement of the it known that it VVILLARDE. PORTER, actuator.

citizen of the United States, residing at The novel and improved construction of Lynn, county oi Essex, State of Massachu my maximum demand indicator will be best setts, have invented certain newand useunderstood by reference to the accompanying ful Improvements in Demand-lndicators, of drawings. which the following is a specification Referring to Fig. l of the-drawings, there My invention relates to demand instru- 13 shown a system of distribution compris struments which indicate the demand and to translating devices '6. A. watthour meter especially the marcnnum deinand made by of the induction ty} e is operatively connectan electrical installation upon a central gened to the system in the usual manner for the eratingstation. or other source of electric pi'lrpose of integrating and registering the energy suppiy. total quantity of energy consumed in the Broadly, the object of my invention is to translating devices. The atthour meter generally improve the present construction; comprises the usual series coil 7 and potenof demand indicators. tial coils 8 which produce a shifting mag More particularly the object of my presnet'ic field proportional to the instantaneous out invention is to provide a novel and'imrate of the consumption of energy, in the liro'ved demand indicator which is of sim- Well understood manner. A rotatable disk pie and compact construction and reliable armature 9 is located Within the influence of in operation. the magnetic field; produced by the coils 7 Other and more specific objects of my and 8. Permanent magnets 10 are mounted present invention will be noted in detail in operative relation to the disk armature 9; so that the revolutions of the armature are The novel and patentuhle features which directly proportional to the Watthours of I believe to be characteristic of my invenenergy consumed in the translating devices. claims appended The speed of rotation of the disk a1 mature 9 hereto. I is proportional to and a measure of the in- The construction and mode of operation stantaneous rateof consumption of energy of a maximum demand indicator embodying in the installation. 7 c my invention. will be understood byrefer- A difterential gearing comprising two to the following description taken in gear members 11 and 12 and a planetary connection with the accompanying drawgee-r member". 13 are operatively mounted ings, 'n which upon pivoted shaft 14. The gear members Figure 1 is a diagran'iinatic View in per- 3.1 and 12 are loosely mounted on this shaft, soective of my improved maximum demand While the planetary gear member 11 is seindicator operatively connected to an eleccured to the shaft by an arm 15 A gear 15 tricel instaliation and Fi 2 is front View is rigidly secured to the gear member 11 and of the scale and indicating member of the is operatively connected through a gear instrument. train 17 to the rotatable shaft 18 of the Watt-- The demand indicator of my present in" hour meter. The gear member 11 ofthe dif vention hclongsito that general of in ferentiel gearing is thus directly connected struments in which measurements interto the disk armature 9 of the watthour disk armature,

My intention more particularity to 19 is rigidly secured to the gear that type of demand indicator in which an "member 12 of the differential gearing and ial or zero position ..;eshes with a pinion 20 secured to sro-. and ada ptcd to be driven by the rotatable tatuhly mounted shaft The shaft 21 also shaftoi .an electric motor meter is inter--coriies at gear meshing with a pinion 23' mittently returned to its initial position. on shaft 24. Em damping vane 25- is Any suitabie recording means is empioy'ed elsc'secnredto the shaft The gears i9,

Patented May It, 19%52 ing conductors supplying electric energy meter end. has'a speed of rotation directly Cll I/J v a I e decreasing ratio directly connecting the gear member 12- of the differential to the damping vane 25.

A. lever arm 26 is secured to a pivoted tit 27 and is provided at one end with. a linger 28. When the lever arm 26 is in the position indicated in Fig. 1 of the drawings, the linger 28 projects into the path a lug 29 secured to the gear 22-. The engagement of the lug 29 with the finger 2S prevents rotation of the gear 22, thereby locking the gear member 12 and preventing its rotation.

A coil spring 30 is secured at one end to the shaft 1 and at the other end to a fixed part 31 of the instrument.

When energized, this spring tends to rotate the shaft 1 1 in a direction opposite to the direction of rotation of the gear member 11. As previously explained, rotation of the gear member 12 is normally prevented because of the engagement of the lug with the finger .23,-th us when the gear member 11 is rotated by the watthour meter the planetary member 13 and the shaft 14 attahed thereto will rotate in a forward direction, as indicated by the arrows in Fig. 1.

The rotation of the gear member 11. operates wind up or energize the spring 30. As previously stated. the tendency of this spring, when energized,-is to drive the shaft 1i and hence the planetary gear member 13 in backward direction. Since the gear or 12 normally locked against rotation. the spring is normally maintained inactive. It will, of course, be understood that the rotation of the shaft 14- in response to the action the spring 30 is relatively ch faster than the rotation of the gear tor shaped r disk is pivotally outed in the same air gap as the disk ar r 9 of the \vatthour meter. The disk is thus subjcctedto the influence of the iii-id produced. by the coils 7 and 8. Moveof the disk is restricted by means of 1 a 36 which projects into a. slot 37 in the The disk is secured. ton pivoted shaft s a counterbalancing memtrol spring has one end se- 33 and the other end so i apted to be driven by 'lhe spring i0 is so arranged Wound p or energized when the member 13 rotates in a forward features of constrhction of novel and improved demand lindicator my will be better understood by a consideration 1e. operation. thereof, When electric env being supplied to the tran slatingdevices a soil magnetic field vvill be produced by the ii .0 coils Z and 8, resulting "i atthour meter armaand 23 thus constitute a gear train of gearing ture 9, and a rotary i'novement of the planetary member 13 and shaftild in a forward direction. A. torque tending to turn the sector disk 35 is also developed and results in moving the disk until one end of the slot 37 engages pin 36, as indicated in the drawings. ,Rotation of the shaft 14 energizes the spring 30 and. also the control spring 40. The action of the control spring i0 when energized is to resist movement of the disk 35 in response to the action of the meter coils. As the control spring is gradually energized by rotation of the Watthour meter shaft its countertorque acting on the shaft 38 will, at some instant, equal the torque resulting from the action of the meter coils. Further rotation of the Watt hour meter shaft will further energize the control spring 40, thereby increasing its countertorque to such an extent that it overcomes the torque acting on the disk 35 and moves the disk until the other end of the slot 37 engages the pin 36. When the shaft 38 is thus turned in response to the action of the spring 40, a pivoted lever is, normally resting on the counterbalancing member 39, is pulled into a slot 43 of this member by means of a spring 55. A dog 44 is secured to the lever arm 4:2 and o-peratively engages a. finger 45 secured to the pivoted shaft 27. When the lever 42 drops intothe slot &3, the dog A, through its engagement with the finger 45, operates to turn the pivoted shaft 27 and move the finger 28 from engagement with the lug 29. This movement of the lever arm 26 and finger 28 is made positiveby means of the spring secured between the dog illand a fixed part of the instrument.

The gear member 12 is thus unlocked. The

spring 30, being energized, now operates to turn the shaftl i and the planetary member 13 in a backward direction. As previously stated, the rotation of the shaft 14: in re sponse to the action of the spring 30 is relatively much faster than the rotation of the gear member 1.1. At this stage of the opera tion the gear member 11 acts, in fact, as if it were stationary or locked, and the gear member 12 therefore rotates in a backward direction due to the backward rotation of the planetary member 13 of the differential gearing. The gear member 12 tends to rotate at a rapid. rate, but its rotation is reoted shaft 27 is arranged in the path of movement of the pin 41-6. VJ hen the shaft 14 and planetary member 13 rotate back- Wardly, due to the action of the. spring 30. the pin 26, rotating counterclockwise as viewed in 1 the drawings/engages ary member 13 and of the shaft 14.

When the control spring has been deencrgized a slight amount its countertorque becomes smaller than the torque exerted on the sector diskby the meter coils; The sec tor disk thereupon responds to the action oi the now dominating meter torque and moves hack into the position indicated in the drawings with the pin 36 engaging the.

lei'tend of the slot 3?, as viewed from the front of the instrument. Theslot 4:3 in the counterbalanciug member 39 has an inclined surface 59 which forces the lever 42 out or. the slot and into the position ind-i-' cated in the drawings when the sector disk responds to the action of the meter torque. It will thus be seenfthat just as soon as the release gear train commences to run out the countertorque of the spring 40 is reduced and the sector disk'35 imriiediatelychanges sides thereby forcing the lever 42 out of the slot 4.3.- This action occurs almost immediately after the release and before the gear train has had time to run out. It will thus be seen that the lever 42 is almost imme-' diately returned to its initial position, as represented in the drawings, while the lever arm 26 is not returned. to the position shown in the drawings until the engagement of the pin 46 with the aim 417. All of the elements or? the instrument are thus returned to their respective initial. positions for the heginning of another interval of demand measurcment and the cycle of operations is repea ted. I

The shaft 14- is opcratively connected at one end through gearing 49 to an actuator 50 which engages non-return pointer 51. When the pointer and actuator-arein en gagement' the former is moved by the latter when the planetary member 13 drives the shaft Ll in a forward direction. A spring presses against the shaft carrying the pointer 51 and frictionally holds the pointer in the position to which it is moved by the actuator. The pointer sweeps across a suitable scale 53 which is graduated in any desired units to indicate the demand. The position of the pointer 51 with respect to the scale thus indicates the maximum movement of theactuator 50 in its forward direction. g

Thev principle of operation of my novel type of demand indicator will, it is be lieved, be understood from the foregoing description. It will be observed that the countertorque equal to the torque developed shaft until its eountertorque equals a torque sector shaped disk 35, pivoted shaft 38, and control spring l0 correspond to the movable; element of an indicating Wattmeter. The torque tending to turn the disk 35 is proportional to the instantaneous rate of consumption of energy in the installation. In an ordinary indicating instrument, the disk 35 would turn until the spring 40 had been energized a suflicient amount to develop a by the instrument coils. According to my novel arrangement, however, the movement of the diski35 is restricted and the control spring is wound up by the watthour meter 89 developed in the disk 35. 'It will be observed that the countertorque of the control spring must not only be equal to the torque developed in the disk 35, but slightly greater in order to move the disk to its other position and to operate the locking means normally preventing rotation of the gear mem-; her 12. .It will be clear that the control spring 40 must be energized an amount substantially proportional to, and hence a measure of, the instantaneous rate of energy consumption in the installation before the actuator 50, the shaft 14 and the planetary. gear member 13 returned to their re-' spective initial positions. The distanpe which the actuator 50; the shaft 14 and the planetary gear member 13 more from their initial positions before the control spring 40 is so energized is substantially propor tional to ant. ameasure of the instantaneous rate of the consumption of energy in the installation It will thus be evident that the actuator 50 is returned to its initial position whenever the distance it is-movecl from such position is substantially a meas- 195 i "spring 40- vvill continually increase in magnitude until it equals and then overcomes the torque exerted upon the sector disk by the meter coils, whereby the release of the actuator-return mechanism is effectedl Again, the spring 40 may be energized to.

a certain extent and the consumption of energy may then fall to a value where the meter torque is smaller than-the torque of the spring, thus eiiecting the release. In the latter case the instantaneous valiieof the energy consumption which results in etiecting the release may be considerably smaller than that represented by the energy stored up in the spring 40 and the extent of 1a.).

" ittomovement of the actuator 50, but it will be apparent that the extent of movement of the actuator 50 is a measure of, some instantaneous value of energy consumption which existed during the interval of measurement for a substantial period of time.

The indicator may very advantageously be considered from another view point. When we. consider this particular kind of demand indicator operating on a perfectly steady load the conditions are ideal and somewhat difierent from What occurs on a fluctuating load. Obviously, it the load were always steady the demand indicator would not be needed, and hence we are most particularly interested in the operation of the indicator on a fluctuating load. However, an explanation of the operation of the indicator on a steady load is helpful in determining and understanding the character of the operation on a fluctuating load. On a steady load the control spring i0 is wound up an amount which is not only a measure of the instantaneous value of theenergy consumption in the translating devices 6 but an amount which also represents a measure of the total quantity of energy consumed in i the translating devices during the interval of measurement. The extent of movement of the actuator 50 will in this case be a measure of the instantaneous value of the energy consumption during any instant of the interval and also a measure of the total amount of energy consumed in the trans lating devices and integrated by the meter during the entire interval. The load to be metered is, however, scarcely ever a constant one, but it is very convenient and reasonably accurate to consider that the pointer 51 indicates the average load for the interval over which the energy consumption was greatest, and to consider the sector disk portion of the device as simply a means for restoring the elements of the indicator, to their respective initial or zero positions at intervals, fairly constant in time because on steady load any deflection is accomplished in equal time. As heretofore explained the release of the actuator return mechanism can be efiiected by the sector disk 35 in two ways,first, on steady load the spring 40 can be wound up until the torque produced by that load and acting on the sector disk is overbalanced, and second, the spring can be wound up a certain amount and then the energy consumption diminished, thereby reducing the torque acting upon the sector disk an amount suliicient to efiiect the release. in the second case the extent of movement of the actuator 50 may not be a veryaccurate measure of the instantaneous value of theenergy consumption which-eh footed the release; On the other hand the extent of movement of the actuator is a measure of the energy consumed during the interval. It will thus be seen that the move ment of the actuator 50 is substantially a measure of the average rate at which energy was consumed during the interval and the release isaccomplished by an instantaneous value of the energy consumption which is ordinarilv approximately near this average value but not exactly like it.

It will be observed from the foregoing description and explanation that I have provided a maximum demand indicator of simple and compact construction. All of the operative elements of the indicator are always directly connected with their cooperating elements and there is no interrupting of gear connections to permit the return of the actuator to its initial position. The movement of the actuator in a backward direction to its initial position is smooth and gradual due to the retarding action of the damping vane 25 and decreasing gear train connecting the gear member 12 to the damping vane. The operative elements of the demand indicator are not numerous and are very compactly arranged, so that all of these elements can be easily included within an ordinary meter casing. As will be observed from the drawings, the sector disk -15 occupies very little additional space in the watthour meter, and can be in cluded in. an ordinary watthour meter of: the induction type without dlliiculty.

Numerous modifications in the details of construction of my improved demand indi-i cator will be evident to those skilled in the art. I do not, therefore, desire to be limited to the specific construction which I have herein illustrated and described by way of example, but I aim in the term of the appended claims to cover all modifications within the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States, is

1.111 a demand indicator, a rotatable meter element, a rotatably mounted member, means for exerting a torque on said member substantially proportional to the speed means adapted when energized to exert a counter-torque on said member, and means whereby said last mentioned means is en ergized by the rotation of the meter element.

2.111 a demand indicator, a rotatable meter element, a rotatably mounted shaft,

means for exerting a torque on said shaft substantially proportional to the speed of rotation .01" the meter element, a spring adapted when energized to exert a counter-- torque on said shaft, and means whereby of rotation of the meter element,

'mentioned means is energized by the rotation of said armature.

4:. In a demand indicator, a rotatable 1 meter element, a member having a restricted 'is energized-"by the element.

movement, means whereby a force is exerted on said member substantially proportional to the speed of rotation of the meter element, means adapted "when energized to exert an opposing force on'said member, and means whereby said last'mentioned means rotation of the meter 5. A maximum demand indicator comprising arotatable meter shaft, an actuator having an initial position and operatively cennectedto the meter shaft, means adapted to be energized by the rotation of the meter shaft, means whereby the actuator is returned to its initial position when the meter shaft has energized said last mentioned means an amount substantially proportional to the speed of rotation of the meter shaft, and, means for indicating the maximum movement of said actuator.

6. A maximum demand indicator comprising arotatable meter element, an actuator having an initial position and adapted to be driven by said element, a movable member adapted to be acted upon by an electrical. torque substantially proportional to the torque acting upon said element, a control spring operatively connected to said member and adapted to be energized' by ,the rotation of said element, means whereby said actuator is returned to its initial position when the torque of said spring slightly exceeds the electrical torque acting upon said member, and means for in d'icatmg the maximum movement of said actuator. I

7. A maximum'demand indicator com.- prising a rotatable meter element, an actuator having an initial position and operatively connected to the meter element, a movably mounted member, means for ex erting a force on said member substantially proportional to the speed of rotation of the .meter element, means adapted when energized to exert an opposing force onsaid member, means whereby said last mentioned means is energized by the rotation of the meter element, and means whereby said actuator is returned to its initial position when the opposing force exerted on said member is slightly in excess of the first mentioned force, and means for indicating the maximum movement of said actuator.

- 8. A maximum demand indicator comprising a rotatable meter element, an actuator having an initial position and operatively connected to the meter element, a pivoted shaft having a restricted movement, means for exerting a torque on said shaft substantially proportional to the instantaneous speul of rotation of diameter-element, means adapted whenenergized to exert acountertorrpie on said shatt', means whereby said last mentioned means is energized by the rotation of the meter element, means whereby said actuator is returned to its inion said shaft overcomes the torque. and

means for indicating the maximum movementof said actuator.

9. A. maximum demand indicator com prising a rotatable meter element, an actuator having an initial position and adapted to be driven by said element. a movable member adapted to be acted upon by an elec triealv torque substantially proportional to the torque acting upon said element. a control spring operatively connected to said member and adaptedto be energized by the rotation of said, element, means whereby said actuator is returned to its initial position when the torque of said spring slightly exceeds the electrical torque acting upon said member, means for damping the move ment of the actuator while it is returning to its initial position, and means for indicating, the maximum movement of said actuator.

10. A maximum. demand indicator comprising an electric meter having: field coils and a rotatable armature, member pivotally mounted. in the magnetic field of said coils whereby the member is subjected to a torque, means operatively related to said member and adapted. when energized to exert a countertorque thereon, means whereby said last mentioned'means is energized by the rotation of said armature an actuator having an initial position and operatively connected to said armature, means whereby said actuator is returned to its initial position when said counter-temple overcomes said torque, and means for indicating the maximum movement of said actuator.

11. A maximum demand indicator comprising an electric meter having field coils and a rotatable armature, a member pivotally mounted in the magnetic field of said coils whereby the member is subjected to a torque, means restricting the movement of said member, a spring operatively related to said member and adapted when energized to exert a countertorque thereon, means whereby said spring is energized by the rotation of said armature, an actuator having an initial position and operatively connected to said armature, means whereby said actuator .tial position when the cguntertorque exerted prising an electric meter having field coils and a rotatable eri'nature, a member pivotally mounted in the magnetic. field of said coils whereby the member is subjected to a torque, 2i spring operetively related to said member and. adapted when energized to GX- ert, e counter-torque thereon, a diiferential gearing having; two gear members and a planetary member, an actuator having an initial position and operetively connected to said planetary member, means operatively connecting said armature to one of said gear members, a spring connected to the second gear member and adapted When energized to return the actuator to its initial position, means 7 both of said springs are energize-n by the rotation of said armature, looking riieans for preventing rotation ofseid second gear member, means for releasing said. iookin means when he eeuntertorque exerted n s 1 comes the torque (i X the maximum. mo.

in witness Wb my hand this 2!,

WVitnesse.

JOHN A. Me SVEN R. 

